1. Field of the Invention
This invention relates to a matrix display of light emitted diodes with a backside that is accessible for light unit insertion and maintenance.
2. Description of the Related Art
FIG. 1 is a traditional light board. The conventional light board is a printed circuit board (PCB) 10 with a plurality of light-emitting diode (LED) chips 11, only one LED 11 is shown in FIG. 1, each of the diodes has bottom metals 11a and 11b. Corresponding metal circuits 10a and 10b are provided on the board 10 to electrically couple with the electrodes 11a and 11b of the light-emitting diode chip 11 respectively to form a traditional light-emitting diode display board. The shortcomings of the prior art are as follows: (1) inflexibility in color changing, i.e., it is impossible or inconvenient to change different light color chips at any moment; (2) inconvenience of maintaining and replacing a failure diode chip.